© DAVID TROOD/GETTI IMAGESHealthy adults secrete roughly 1 to 1.5 liters of saliva each day from three major pairs of glands that are in close contact with the bloodstream. Mostly water, spit also contains electrolytes and proteins, including glycoproteins that form mucus, enzymes that break down food and bacteria, and secretory antibodies.
Besides maintaining our oral health, saliva harbors clues about our ancestry and whether we might be fighting an infection, are overstressed, or have a hormonal imbalance. In the future, the watery fluid may even provide a rapid screen for a recent heart attack or distinguish between bacterial and viral infections. Indeed, characterizing the oral microbiome, the collection of all of the microorganisms in a person’s mouth, and its potential links to health and disease is its own emerging field. (See “The Body’s Ecosystem,” The Scientist, August 2014)
“In the past few years, there’s been a lot more optimism about what can be done [using] saliva,” says Paul Slowey, CEO of Oasis Diagnostics in Vancouver, Washington. That’s because technologies are now sensitive enough to detect and ...
